1. Field of the Invention
The present invention relates to a hook cable used for a fixing method with respect to an atlantoaxial joint unstable symptom between a first cervical vertebra (an atlanto) and a second cervical vertebra (an epistropheus), and a system for fixing the same.
2. Description of Related Art
As a method of fixing an atlantoaxial joint between an atlanto (a first cervical vertebra) 1 and an epistropheus (a second cervical vertebra) 3, for example, as shown in FIGS. 1A and 1B, there is executed a method of obliquely screwing and inserting a pair of right and left screws 9 to lateral roots 7 of the atlanto 1 from an inferior articular process 5 of the epistropheus 3, aligning right and left autologous bones 15 between an arcus posterior 11 of the atlanto 1 and an arcus vertebrae 13 of the epistropheus 3, and fastening the arcus posterior 11 and the arcus vertebrae 13 by a titanium wire 17.
As described above, in the related art, since it is necessary to wind the titanium wire 17 around the arcus posterior 11 of the atlanto 1 and the arcus vertebrae 13 of the epistropheus 3, it is hard to perform the winding operation, and since it is necessary to pay attention so as to prevent such as a bone resection loss or a breakage of the titanium wire 17 from being generated at a time of fastening the titanium wire 17, there is a problem that it is necessary to pay attention to the fastening operation.
The present invention is made by taking the problem as described above into consideration. According to a first aspect of the present invention, there is provided a hook cable provided with a hook for hooking to an arcus posterior in an atlanto, wherein a cable which can freely bend is integrally provided in a base portion of the hook.
In the hook cable as described in the first aspect, the structure is made such that the hook is provided with a projection on a surface hooked to the arcus posterior.
According to a third aspect of the present invention, there is provided a system for fixing an atlantoaxial joint, in which a screw hole is provided in a head portion of a screw freely inserting to an atlanto from an epistropheus, an engagement groove communicated with the screw hole is provided, a cable provided in a hook freely hooked to an arcus posterior in the atlanto is provided so as to be freely engaged with the engagement groove, and a fixing screw freely fixing the cable engaged with the engagement groove is provided so as to be freely meshed with the screw hole. The structure is made such that a screw portion is provided in an inserting direction of the screw, and a guide hole is provided in an axial core of the screw.